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91.
Reactions of chloroacetamides (5) with N,N‐dimethylformamide dimethyl acetal gave 1,4‐diaryl‐piperazine‐2,5‐diones 11a–e in good yield, rather than 1,5‐diaryl‐3,7‐dimethoxy‐1H,5H‐[1,5]diazocine‐2,6‐diones (9a–e). 相似文献
92.
Ahmed I. Khodair Ahmed Swelim A. A. Abdel-wahab 《Phosphorus, sulfur, and silicon and the related elements》2013,188(1-3):169-171
Abstract The reaction of methane- and ethanesulfonyl chloride with selected diarylcadmium compounds was investigated. In contrast with arenesulfonyl chlorides which react with diarylcadmium to give sulfones in appreciable yields, ethanesulfonyl chloride did not yield sulfones. Methane-sulfonyl chloride gave sulfones in very poor yields. The major products were haloarenes, alkane-sulfinic acids and biaryls. Cross-over experiments revealed that the formation of biaryls involve an inter-not intra-molecular reaction (cf. eq. 4). 相似文献
93.
Priya Malshe Maryam Mazloumpour Ahmed El-Shafei Peter Hauser 《Plasma Chemistry and Plasma Processing》2012,32(4):833-843
In this study, diallyldimethylammonium chloride (DADMAC), a quaternary ammonium salt monomer, is graft polymerized on 50?C50 Nylon-Cotton (NyCo) standard military fabric using atmospheric pressure glow discharge plasma to impart self-detoxification capability. Atmospheric pressure plasma?is used to induce free radical chain polymerization of the DADMAC monomer to introduce a graft polymerized network on the fabric with durable antimicrobial properties. Pentaerythritol tetraacrylate (PETA) is used as a cross-linking agent to obtain a highly cross-linked, durable polymer network. The presence of polyDADMAC on the fabric surface is confirmed using acid dye staining, SEM, and TOF?CSIMS. Antibacterial performance is investigated using standard AATCC Test Method 100 for both gram positive and gram negative bacteria. Results show 99.9?% reduction in the bacterial activities of Klebsiella pneumoniae and Staphylococcus aureus. 相似文献
94.
A solvent-free, eco-friendly and facile approach for the synthesis of highly functionalized tetrasubstituted pyrroles has been reported through one-pot four-component reaction of aldehyde, amine, nitroalkane and 1,3-diketone using silica gel supported polyphosphoric acid (PPA–SiO2) under microwave condition. The reaction occured through the in situ formation of β-keto enamine and nitrostyrene analog following Michael addition and finally intramolecular annulation affording the products in good yields. The key features of the present method include clean reaction, mild conditions, low catalyst loading, straightforward, high to excellent yields, short reaction time, avoiding use of harmful metal catalyst and organic solvent, environmentally friendly compared to the existing methods, recovery and reusability of catalyst and easy workup procedure. 相似文献
95.
96.
Several binary systems made from two laterally substituted azo/ester isomers, namely 2?- (and 3?-) methyl-4-substituted phenyl 4?-(4?-alkoxyphenylazo) benzoates, where the length of the terminal alkoxy group = 8 and 16 carbons, while the other terminal substituent, X, varies between CH3O, CH3, H, Br and CN groups, were investigated using differential scanning calorimetry (DSC) and phases identified by polarised light microscope (PLM). For the sake of comparison, two another binary systems made from 2?- (or 3?-) methyl-4-substituted phenyl 4?-(4?-alkoxyphenylazo) benzoates (n = 8 and X = CH3) each was mixed with its laterally neat analogue and similarly investigated. Results were discussed on the basis of constructed phase diagrams whereby various mesomorphic properties were observed dependent on X, n, and position of the lateral methyl group. In most of the cases, the mixtures exhibited eutectic compositions, while linear or nearly linear nematic and smectic A-composition temperature dependence were observed. 相似文献
97.
Ahmed Jasim M. Al-Karawi Ali Jasim Hammood Adil A. Awad Al-Ameen Bariz OmarAli Saba Riad Khudhaier Dhafir T. A. Al- Heetimi 《Liquid crystals》2018,45(11):1603-1619
The following organic and organic–inorganic hybrid compounds were prepared as photo-luminescent materials following efficient and practical synthetic methods: 1,3-bis[4-(n-alkoxy)phenyl]-2-propen-1-one (where, n-alkoxy: O(CH2)nH, n = 6,7,8,9 or 10); 3,5-bis[4-(n-alkoxy)phenyl]-1H-pyrazole (where, n-alkoxy: O(CH2)nH, n = 6,7,8,9 or 10) (in case of n = 7, a mixture of 3,5-bis(4-heptyloxyphenyl)-1H-pyrazole and 3,5-bis(4-heptyloxyphenyl)-4H-pyrazole was detected) and bis(3,5-bis [4-(n-alkoxy) phenyl]-1H-pyrazole) silver(I) nitrate (where, n-alkoxy: O(CH2)nH, n = 6,7,8,9 or 10). The prepared compounds have been characterised and their structures were elucidated depending upon (FTIR, UV-Vis, 1HNMR, 13CNMR, 2D 1H-1H-COSY, 2D 1H-13C-HSQC and mass spectra) in addition to molar conductivity measurements for silver(I) complexes. The mesomorphism behaviour of the prepared compounds was studied using polarised light optical microscopy and confirmed with differential scanning calorimetry and X-ray powder diffraction techniques. The studies showed that among all of these compounds only the pyrazole derivatives are liquid crystal materials. The luminescent properties of all the prepared compounds were also investigated which confirmed that all of these compounds are photo-luminescent in the crystalline solid state and in the mesophase. 相似文献
98.
In this work, we report the synthesis of porous activated carbon (AC). AC was derived from rotten carrot, at different values of activating temperature under inert atmosphere, employing chemical activation method and ZnCl2 as activation agent. On the basis of results observed by surface area and pore size analysis, effect of activation temperature on synthesized AC was determined. Other material properties such as morphology, thermal stability, vibrational response, and crystal structure of prepared AC were studied using standard techniques of material characterization. Further, the electrochemical performance of synthesized AC was studied as an electrode, in aqueous, organic and ionic liquid based electrolyte. It was found that the synthesized AC based electrode exhibits highest specific capacitance (135.5?F?g?1 at 10?mHz) in aqueous electrolyte and highest specific energy (29.1?Wh?kg?1 at 2.2?A?g?1) and specific power (142.5?kW?kg?1 at 2.2?A?g?1) in ionic liquid based electrolyte. This shows the suitability of synthesized material for use in energy storage applications. 相似文献
99.
Omar U. Ahmed Farouq S. Mjalli Al-Wahaibi Talal Yahya Al-Wahaibi Inas M. Al Nashef 《Journal of solution chemistry》2018,47(3):468-483
In the pursuit of better solvents for use in the extractive desulfurization (EDS) of liquid fuel, the pyrollidinium and phosphonium based ionic liquids (ILs) have been improved by combining them with selected molecular compound modifiers. The modifiers, which are imidazole, poly(ethylene) glycol (PEG 200) and sulfolane were selected to induce previously nonexistent mechanisms in the presence of refractory sulfur compounds. The addition of PEG 200 and sulfolane were observed to have a more positive impact on the performance of the ILs than the addition of imidazole under the same conditions. This provides further support for the idea that π–π interaction may not be the predominant interactions for the ILs that are the highly effective in EDS. Using the sulfolane modified tetrabutylphosphonium methanesulfonate [P4444][MeSO3], up to 81% dibenzothiophene (DBT) removal was recorded at a temperature of 30 °C and solvent-to-mass ratio of 1:1 and after a 30 min mixing time. 相似文献
100.
E. H. Borai I. M. Ahmed A. M. Shahr El-Din M. S. Abd El-Ghany 《Journal of Radioanalytical and Nuclear Chemistry》2018,316(2):443-450
The present work succeeded to develop new optional procedures to enhance the separation process of thorium and REEs. Selective precipitation of thorium with pyrophosphate was successfully attained for the upscale level in which, complete and efficient thorium separation (99%) was achieved with relatively low co-precipitation of REEs (average 15%) and Fe(III) (2.6%). On the other hand, promising and costless method has been developed to optimize the selective precipitation of REEs by adjusting the ratio of the free acids H2SO4 to H3PO4 at 5:1. It could be obviously demonstrated that about 65.3% of LREEs could be precipitated with a minor amount of thorium 11.9%. Finally, this proposed method could be successfully applied for production of Th and REEs with relatively high yield and purity in addition to low-cost–benefit. 相似文献